Ubuntu 12.04 LTS - Benchmarking All The Linux File-Systems
The Bootchart numbers come down to:
Btrfs: 19.30 seconds
EXT2: 11.98 seconds
EXT4: 11.85 seconds
JFS: 11.86 seconds
ReiserFS: 11.62 seconds
XFS: 12.40 seconds
Interestingly, Btrfs was the only file-system that led to a significantly slower boot-time than the rest of the file-systems. The Btrfs file-system had more work to do to get started even though its disk throughput was higher. The disk throughput with Btrfs on boot topped out at 266MB/s compared to XFS at 250MB/s or EXT4 at a reported 248MB/s.